The goal of the trial was testing the effects of a blend of organic acids and essential oils dietary supplementation on growth performance and gut healthiness in broiler chickens. In total, 420 male Ross 308 chicks (1-day old) were randomly assigned to two dietary treatments: basal (BD) and organic acids and essential oils (OA&EO) diets (three replicates/treatment; 70 broilers/replicate). BD group received commercial diets whereas OA&EO group basal diets + 5 g/kg of microencapsulated organic acids and essential oils. OA&EO treatment improved the average daily gain (p < 0.01) and feed conversion ratio at 37–47 days compared to BD treatment. OA&EO treatment improved gut morphology mostly at ileum and duodenum levels in terms of villi height, crypt depth, number of villi, mucosa thickness and villi area at 24 and 34 sampling days. A certain selective action against Clostridium perfringens in ileum of OA&EO group was shown at 33 (p = 0.053) and 46 days (p = 0.09) together with lower median values for Enterobacteriaceae, Enterococci, Mesophilic bacteria and Clostridium perfringens at ceca level. Overall, organic acids and essential oils supplementation improved growth performance in the final growth stage and some morphological gut traits and reduced to a certain extent Clostridium perfringens count in ileum.
1 January 2011 in Cellular Physiology and Biochemistry
It has been shown that MDCK cells, a cell line derived from canine renal tubules, develop cell domes due to fluid pumped under cell monolayer and focal detachment from the adhesion surface. In vitro studies have shown that primary cilia of kidney tubular epithelial cells act as mechanosensors, increasing intracellular calcium within seconds upon changes in fluid shear stress (SS) on cell membrane. We then studied the effect of prolonged SS exposure on cell dome formation in confluent MDCK cell monolayers. A parallel plate flow chamber was used to apply laminar SS at 2 dynes/cm(2) to confluent cell monolayers for 6 hours. Control MDCK cell monolayers were maintained in static condition. The effects of Ca(2+) blockade and cell deciliation on SS exposure were also investigated. Seven days after reaching confluence, static cultures developed liquid filled domes, elevating from culture plate. Exposure to SS induced almost complete disappearance of cell domes (0.4±0.8 vs. 11.4±2.8 domes/mm(2), p < 0.01, n=14). SS induced dome disappearance took place within minutes to hours, as shown by time-lapse videomicroscopy. Exposure to SS importantly affected cell cytoskeleton altering actin stress fibers expression and organization, and the distribution of tight junction protein ZO-1. Dome disappearance induced by flow was completely prevented in the presence of EGTA or after cell deciliation. These data indicate that kidney tubular cells are sensitive to apical flow and that these effects are mediated by primary cilia by regulation of Ca(2+) entry in to the cell. SS induced Ca(2+) entry provokes contraction of cortical actin ring that tenses cell-cell borders and decreases basal stress fibers. These processes may increase paracellular permeability and decrease basal adhesion making dome disappear. Elucidation of the effects of apical fluid flow on tubular cell function may open new insights on the pathophysiology of kidney diseases associated with cilia dysfunction.
Mycoplasmas are recognized as avian pathogens, which may cause both respiratory disease and synovial infections in poultry, resulting in severe economic losses. Our study aims to determine the occurrence of Mycoplasma gallisepticum (MG) and Mycoplasma synoviae (MS) among commercial and rural laying hens located in Ragusa province (South Italy), using a duplex real time PCR. Four hundred tracheal swabs were collected from seven commercial (200 swabs) and 25 rural (200 swabs) farms without any clinical disease history. Out of 400 swabs collected, 50 (12.5%) and 93 (23.25%) were positive for MG and MS, respectively. In particular, 9 (18%) and 22 (23.65%) positive swabs for MG and MS, respectively, originated from commercial farms, compared to 41 (82%) and 71 (76.34%) obtained from rural farms. Data obtained show a lower prevalence of MG than MS in the studied farms. Moreover, both pathogens were spread in rural and commercial farms. PCR could be concluded as a rapid and sensitive method for the identification of MG and MS in areas where commercial farms that are declared Mycoplasma-free and rural flocks coexist. These data highlight the importance of surveillance also in rural poultry to monitoring the occurrence of mycoplasmas strains in strategic productive districts.
Canine adenovirus type 1 (CAdV-1) is the causative agent of a systemic and potentially fatal viral disease of domestic and wild canids. In Italy, CAdV-1 infection has also been occasionally described in dogs, but information on the epidemiology and its genomic features is still limited. A study was conducted on 291 dogs suspected of infectious gastrointestinal disease. Samples collected from dogs in southern Italy between 2017 and 2020 were analyzed. Virological and histopathological assays were carried out. The presence of CAdVs and other canine viral enteropathogens was investigated, and sequence and phylogenetic analyses were performed. CAdV-1 was detected in six (2.1%) dead stray dogs alone or in mixed infections with other viruses. Gross lesions and histopathological findings referred to CAdV infection were observed, also involving the central nervous system tissues. All inoculated samples were successfully isolated. Sequence analysis evidenced divergences with the circulating strains previously described in Italy and a closer relation with older CAdV-1 strains collected from other countries, suggesting a genetic heterogeneity of CAdV-1 in Italy. The evidence of the circulation of CAdV-1 and its genomic features allows us to have more in-depth knowledge of the epidemiology and evolution of the CAdV-1 genomic variants.